The invention relates to a tool for fine machining surfaces, such as cleaning, grinding or polishing. The tool comprises a working medium carrier provided at the bottom face with an attachment side. A set of individually exchangeable strip-shaped lamella holders holding bundled or individual lamellas are attached to the attachment side. The lamellas are oriented away from the working medium carrier and form in downward direction a common working plane.
Such a tool is disclosed, for example, in US 2015/0209938 A1. Tools of this kind, in which working media for fine machining surfaces are attached to strip-shaped lamellas and are secured by strip-shaped lamella holders, provide in comparison to simple abrasive paper sheets great quantities of working medium and also a greater volume for material that is removed by surface fine machining; therefore, they provide longer service life of the tool due to extended wear cycles.
Still, even for tools with lamellas, wear-based exchangeability of the lamellas is to be provided when a complete exchange of the tool is not possible as an alternative. In comparison to a complete tool exchange, the exchangeability of individual lamellas has however the advantage that only individual damaged or worn lamellas can be exchanged without great expenditure. Moreover, the exchange of individual lamellas provides the possibility of attaching to the tool mixed working media that are specific to a given application. Finally, individual exchangeable lamellas or lamella bundles, held by a strip holder, provide the manufacturer with design possibilities already in connection with tool configuration by means of a uniform working medium carrier for various tools with application-specific individual sets of lamellas. It is understood that usually, as is common practice, the lamellas are bundled, i.e., several are combined, and together held by a lamella holder, even though in principle also an individual lamella strip can be connected to a lamella holder.
The tools considered here are in practice mostly rotary tools in which the tool holder is provided with a standardized drive connector and, by means of the drive connector, is to be connected to a rotary drive, for example, a hand-held power drill. Such a tool is typically shaped like a circular disk with a centrally arranged drive connector. In general, a tool can also be configured to perform oscillating movements of the lamellas by means of an appropriate drive connector for a corresponding drive and, in this context, the working medium carrier can also have angular basic shapes. Finally, a tool of the kind considered here can also be a manual tool, without drive connector but provided with a grip or handle.
In US 2015/0209938 A1, the individually exchangeable lamella holders together with the lamellas held by the lamella holders are pushed lengthwise into open-end grooves in the working medium holder. In this context, the lamellas pass through narrow slots at the attachment side and project from the grooves. The grooves are open at the top and covered by a cover that closes off the grooves together with the lamellas contained therein. This design of the tool enables variable configurations of the lamellas already during manufacture and when replacing the lamellas and is also simple and inexpensive with respect to manufacture of the tool support. However, the required secure and fixed attachment of the corresponding cover for securing the lamellas requires diligence. In particular, the design of the continuous open grooves at top and bottom causes a weakening of the working medium carrier that limits the robustness of the tool for surface machining and increases the necessary diligence when mounting the tool upon exchange of the lamellas.
It is the object of the invention to design a tool of the aforementioned kind in a more robust construction and with a simpler design in regard to furnishing the tool wilt lamellas during manufacture but also during use of the tool, in particular for exchange of the lamellas, while maintaining a simple configuration that is advantageous for large volume production.